merge fix

Jenkinsfile

@@ -276,7 +276,7 @@ pipeline {
                     agent {
                         docker {
                             image 'stanorg/ci:gpu'
-                            label 'linux'
+                            label 'linux && gpu'
                             args '--pull always --gpus 1'
                         }
                     }

src/stan/callbacks/dispatcher.hpp

@@ -12,6 +12,7 @@
 #include <type_traits>
 #include <variant>
 
+
 namespace stan {
 namespace callbacks {
 

src/test/unit/callbacks/dispatcher_test.cpp

@@ -11,8 +11,8 @@
 #include <Eigen/Dense>
 
 // For this test we assume that InfoType has at least these values:
-using stan::callbacks::InfoType;
 using stan::callbacks::dispatcher;
+using stan::callbacks::InfoType;
 
 struct deleter_noop {
   template <typename T>
@@ -21,14 +21,15 @@ struct deleter_noop {
 
 class DispatcherTest : public ::testing::Test {
  public:
-  DispatcherTest() :
-      ss_sample(),
-      ss_config(),
-      ss_metric(),
-      writer_sample(ss_sample),
-      writer_config(ss_config),
-      writer_metric(std::unique_ptr<std::stringstream, deleter_noop>(&ss_metric)),
-      dispatcher() {}
+  DispatcherTest()
+      : ss_sample(),
+        ss_config(),
+        ss_metric(),
+        writer_sample(ss_sample),
+        writer_config(ss_config),
+        writer_metric(
+            std::unique_ptr<std::stringstream, deleter_noop>(&ss_metric)),
+        dispatcher() {}
 
   void SetUp() {
     ss_sample.str(std::string());
@@ -146,6 +147,29 @@ TEST_F(DispatcherTest, StructuredBeginEndRecord) {
   // JSON output should contain opening and closing braces
   EXPECT_NE(output.find("{"), std::string::npos);
   EXPECT_NE(output.find("}"), std::string::npos);
+=======
+TEST_F(DispatcherTest, MetricStructuredKeyValueRecord) {
+  // For METRIC (structured writer), open a record, dispatch key/value pairs,
+  // then close the record.
+  dispatcher.begin_record(InfoType::METRIC);
+  dispatcher.dispatch(InfoType::METRIC, "metric_type", std::string("diag"));
+  dispatcher.dispatch(InfoType::METRIC, "stepsize", 0.6789);
+  // For the inv_metric, assume the caller converts the vector to a
+  // comma-separated string.
+  std::vector<double> inv_metric = {0.1, 0.2, 0.3};
+  std::string inv_metric_str;
+  for (size_t i = 0; i < inv_metric.size(); ++i) {
+    inv_metric_str += std::to_string(inv_metric[i]);
+    if (i != inv_metric.size() - 1)
+      inv_metric_str += ",";
+  }
+  dispatcher.dispatch(InfoType::METRIC, "inv_metric", inv_metric_str);
+  dispatcher.end_record(InfoType::METRIC);
+  // Expected output:
+  // Begin record marker, followed by key/value pairs each formatted as
+  // "key:value;" and then end record marker.
+  std::cout << ss_metric.str() << std::endl;
+>>>>>>> 89d756b23a601c560cb63a09930f5fcbce011efc
 }
 
 // Test structured writer key-value pairs with string value
@@ -159,6 +183,7 @@ TEST_F(DispatcherTest, StructuredKeyStringValue) {
   EXPECT_NE(output.find("value1"), std::string::npos);
 }
 
+<<<<<<< HEAD
 // Test structured writer with multiple key-value types
 TEST_F(DispatcherTest, StructuredMultipleValueTypes) {
   dispatcher.begin_record(InfoType::METRIC);